Leopard infection fuels fears of spillover

A male leopard cub found dead in the wild in mid-October has been detected with the novel coronavirus in India, marking the first reported incidence of the virus in a free-ranging wild feline species.

Researchers at the Indian Veterinary Research Institute, or IVRI, in Uttar Pradesh revealed the findings on the leopard cub found dead near Bijnor, around 150 kilometers from New Delhi.

Genomic sequencing of samples from the carcass of the cub revealed that it was naturally infected with the Delta variant, according to a report prepared by the researchers. The report was posted on Jan 12 on bioRxiv, a preprint server for biological studies.

Free-ranging animals

The report warns of possible spillover of the infection from humans to free-ranging animals.

Scientists had also detected coronavirus among captive lions and tigers, as well as in wild mink and deer.

The discovery of coronavirus in the dead leopard cub has triggered concerns among the researchers who say their findings underline the need to intensify the screenings of wild feline species to keep track of the virus' evolution and the development of carrier status of coronavirus among wildlife species.

"We found that this cub had COVID infection, but it did not die of COVID. We did find that the pathogenesis of the infection in leopards is similar to what is seen in humans," said Gaurav Sharma, one of the researchers.

"However, we do not yet consider this to be an animal reservoir, since the infection is not widespread and animals do not seem to be transmitting among one another."

It is important to find out how the cub was infected with Delta, Sharma said.

The carcass of the leopard cub, which was estimated to be 1 year old, was recovered during routine work in the agricultural fields of Mojipur village in the Social Forestry Division of Bijnor.

During the necropsy examination, the Indian Agricultural Research Institute and the IVRI found canine teeth marks on the cub's neck, contusions under the skin and hemorrhaging on the neck and head－suggesting a case of infighting.

Researchers said the cub might have died after a fight with other animals some time after it began showing symptoms.

"The virus is finding new hosts in some wild animals. Many experts believe it may become endemic and can't be wiped out completely as it finds new animal hosts," Sharma said.

The writer is a freelance journalist for China Daily.